diff --git a/.github/workflows/dotnet.yml b/.github/workflows/dotnet.yml
index 4ecdafa..15d965d 100644
--- a/.github/workflows/dotnet.yml
+++ b/.github/workflows/dotnet.yml
@@ -67,7 +67,8 @@ jobs:
     - name: Generate version tag
       id: version
       run: |
-        TAG="v1.$(date -u +%y).${{ github.run_number }}.$(date -u +%m%d)"
+        BUILD_NUM=$(( ${{ github.run_number }} + 500 ))
+        TAG="v1.$(date -u +%y).${BUILD_NUM}.$(date -u +%m%d)"
         echo "tag=$TAG" >> "$GITHUB_OUTPUT"
         echo "Version: $TAG"
 
diff --git a/JobTracker.csproj b/JobTracker.csproj
index ad3ea45..8160576 100644
--- a/JobTracker.csproj
+++ b/JobTracker.csproj
@@ -5,13 +5,15 @@
     <Nullable>enable</Nullable>
     <ImplicitUsings>enable</ImplicitUsings>
     <BlazorDisableThrowNavigationException>true</BlazorDisableThrowNavigationException>
-    <!-- Version: 1.YY.BuildNumber.MMdd
+    <!-- Version: 1.YY.BuildNumber+500.MMdd
          MSI only compares the first 3 fields for upgrade detection (4th is ignored).
          The build number (which changes every CI run) MUST be in the 3rd field,
          otherwise same-day builds produce duplicate entries in Apps & Features.
-         CI uses github.run_number; local builds fall back to HHmm. -->
-    <BuildRevision Condition="'$(BUILD_NUMBER)' != ''">$(BUILD_NUMBER)</BuildRevision>
-    <BuildRevision Condition="'$(BUILD_NUMBER)' == ''">$([System.DateTime]::Now.ToString("HHmm"))</BuildRevision>
+         CI uses github.run_number; local builds fall back to HHmm.
+         BuildOffset ensures new versions (1.26.500+) are higher than old scheme (1.25.MMDD). -->
+    <BuildOffset>500</BuildOffset>
+    <BuildRevision Condition="'$(BUILD_NUMBER)' != ''">$([MSBuild]::Add($(BUILD_NUMBER), $(BuildOffset)))</BuildRevision>
+    <BuildRevision Condition="'$(BUILD_NUMBER)' == ''">$([MSBuild]::Add($([System.DateTime]::Now.ToString("HHmm")), $(BuildOffset)))</BuildRevision>
     <Version>1.$([System.DateTime]::Now.ToString("yy")).$(BuildRevision).$([System.DateTime]::Now.ToString("MMdd"))</Version>
     <DefaultItemExcludes>$(DefaultItemExcludes);JobTracker.Tests\**</DefaultItemExcludes>
     <ApplicationIcon>wwwroot\favicon.ico</ApplicationIcon>